Would you not theoretically gain a slight efficiency advantage with higher voltage (ie. less heat produced by the ballasts)?

If there is something like that, my guess is it's minimal or negligible. Of all the stats/specs I read about ballasts, they all more or less have the same "wattage" (which is roughly amps times voltage, give or take) regardless of what input voltage is used.

Thus I'm not real sure that it's a "benefit" nor a "deteriment" to run them off 220. Like powerboy said, it's half the amps, but it's twice the voltage. Six of one, half-dozen of the other? I guess it's more a matter of whatever's convenient. If you have to run some new circuits/wiring/breakers anyways, you might as well just do the one for 110 and be done.

But, on the other hand, .... the wiring for 220 is presumably going to be heavier guage and thus there ought to be less resistance in the wiring. Therefore it might be conceivable that there is some slight gain in efficiency (rather, a reduction of loss, or something like that), but I can't imagine if that really translates into a noticeable reduction in your power consumption... I have no idea.

Well put in a circular sort of way!! :smile:

I think the bennifit of running 220 volts is you can pretty much run twice the equipment on a circuit, IE if you can run 15 amps on a 20 amp circuit @120 volts you can run twice the equipment (as long as it's rated for 220v) on a 220v circuit to make that 15 amps.

maybe not?

Doug

yes, thats pretty much what it boils down to. amps drawn are half, so you can essentially double the load.

just remember, at startup, theres quite the surge of power, so keep that in mind when calculating.

as for power consumption, its going to be the same regardless. what bc hydro pumps into our houses is single phase power, and its quite inefficient.

theres an equation used by the hydro companies to allow for wasted power (i think its called the pfc. power factor correction) essentially its for situations when current drawn doesnt follow the voltage (goes out of sync) in any case, its to their benefit..

im getting to technical for myself here :)

i guess my point is, 220v is great. if you have the opportunity to use it do so!

I'm not sure I get it. Does the pfc. (or whatever) value have any bearing?

Ok. Let me try it this way... So if I was going to install a subpanel in a tank room, I'd use a 220V feed for that and have separate breakers for each 110V circuit. If I had that, then conceivably I might just leave a 220 circuit for the ballasts and any pumps I had that might run off 220.

But assuming that I don't currently have the subpanel, and don't have any equipment that runs off 220, I don't know that I see a benefit to the effort of installing one 220V circuit. The lights aren't going to burn any brighter, the ballasts aren't going to run any less hot, the watts consumed aren't going to be any less. Essentially, it comes down to "what plug do I want to use?"

The "double your load" thing really only strikes me as a benefit if I was on the borderline of overloading one circuit. In which case, I might just string myself some extra circuits anyways and just do a careful load balance to begin with?

i started the pfc topic to illustrate that power delivery is not efficient, and when more is drawn, the less efficient it gets. this was to dispell the notion that there was a cost savings involved by using less amps.



the benefit is safety and convenience. when you deal with power, the arguments should not be "The lights aren't going to burn any brighter, the ballasts aren't going to run any less hot, the watts consumed aren't going to be any less" it should be, how can i minimize overload.

the whole function of the breaker is to not protect the appliance plugged into it, it is to protect the wire. now if you watch any home show these days, ie holmes on homes etc, you will take note to how shoddy peoples work can be.. i have seen some absolutely horrible house wiring that shouldnt be in the walls, but yet there it is.

this will be my last post on this topic as it seems were flogging a dead horse here..

my personal experience dictates running a seperate line to something which is going to draw more current than normal.. so this is why i push it.. (most electricans will agree) if your current set up works for you and you see no need to change, then thats ok as well :)
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I don't think we're flogging a dead horse. I think it's been interesting so far.

First of all I'm not sure that I am in disagreement at all about:

That's exactly what I was thinking, too. I would try to minimize overloading any one circuit by spreading the load onto different circuits. Personally, if I was anywhere near a 15amp load on a single circuit, I'd be very nervous about that. I'm much rather, for example, see 12amps split between two circuits, instead of all on one circuit.

It seems me that you're saying that one can take this one step further, instead of putting "this and that on circuit #1" and "this other thing and that other thing on circuit #2", we're now putting "half of this one item on circuit #1" and "the other half of this one item on circuit #2." If my device had a serious amperage draw by itself then I understand why you would want to do this. But the typical amp draw for metal halides is going to be in the 2-4 amp ballpark, which to me, seems not entirely unreasonable to have one or two of these on a circuit and then be done with it.


Is 220V inherently safer than 110V? If we're going to introduce variables such as "shoddy wiring" then it seems to me that 220V is potentially "twice as dangerous" as 110V. Convenience be one thing, efficiency be other thing, and safety be yet another thing.


I think they are still valid questions though. Even if the answer is "it won't make a difference" they should still be asked. If it's better to do "function 'X'" in one method over another, why not pursue that?

My thinking was that as far as the "overall efficiency" (which I, personally, measure in terms of "what did the utility company charge me this month"), 220V vs. 110V won't make any significant difference. Nothing in the ensuing discussion since the question was originally asked, has suggested otherwise. The only good reasons have been about load balancing and minimizing overload. If one's circuits are not closely approaching their limits then I don't see a burning need to rip apart my house and install a 220V circuit. If they were, however, taxed close to their limits, or perhaps I was building a new tank room that I wanted to service who-know-what-kind-of-future-needs, then yes, I see the "benefit."

looks like it isnt my last post :)

and im not at all upset, just feels like my point isnt being conveyed.


for a second, try to forget voltage.. its just another way to deliver the current.. the amps are what is important. this all depends on whats going on with the main panel in your house, the age of the hardware, etc.

if you have a 100 amp main service, and your house isnt drawing tons of power, then keep it with what you have.. the reason to go with 220v is when amps are at a premium, and/or safety.

if you look at whats in your main panel, you will see lots of single pole 120v breakers with 14gauge(min code) wire going from them to wherever it leads.. now, each break in the line adds to resistance. resistance equals heat. heat makes the breaker trip (as well as amps) if its wired correctly, all is well and life goes on.

now each 400 watt ballast puts out about 5 some odd amps at startup and settles down to about 4ish i believe (120v)

put two on there and you now have pretty much maxed the circut.. not to mention the other breaks in the line ie other recepticles etc.. then you have to look for other sources of power, so what do we do? we run extention cords.. which are not at all designed to carry power for a long time.. they are for instant power then to be put away.. this is why the wire is stranded.. not very efficient.. all of this creates a network of heat from multiple places with potential for multiple problems.

now i realize its not practical in most cases to just run another line and tear up walls etc. we are far to use to just "plugging it in and hope for the best" so to speak

electricity is quite dangerous, and we as the consumer are not educated enough on the topic. its a harmonious balance to keep electricity in check.. just "plugging it in and trusting existing wiring" is certainly not for me.

in an ideal world we would all run 220v sub panels to our tanks and have one source of power to draw from. this is the way to do it, but as we all know not feasable in most cases.

i guess the nuts and bolts comes down to.. does using a dedicated line make sense to the average hobbiest who is drawing only 10 amps, certainly not.

does it make sense to the person who is drawing 30amps @120 volts? it does indeed..

3 400w ballasts, a few pumps and a heater or two and your there. (i didnt even mention people with chillers)

its not hard to add up the amps with todays toys :)

always air on the side of caution when dealing with electricity..

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Thanks for the info..

:mrgreen: Too true ....


I cannot even imagine putting all that on one breaker! For me, you just described at least 3 or 4 separate breakers.

I do like the 220V subpanel idea...

cheers